WASHINGTON — The 91 veterans on an Honor Flight from Mississippi weren’t going to be denied the chance to see the memorial built for them.

Arriving on four charter buses at Washington’s National Mall Tuesday morning on the first day of a federal government shutdown, the vets found the World War II monument barricaded and its fountain idle. A sign on the fence read “Because of the Federal Government SHUTDOWN, All National Parks Are CLOSED.”

Honor Flights fly veterans in and out the same day, meaning for most this was their final opportunity to see the memorial. With a bagpipe escort, the veterans ignored the barriers and walked or were pushed in wheelchairs to see the column for Mississippi. Park Police stood by, watching.

“This is ridiculous,” said Tom Bratner, 89, who served as a Seabee during the liberation of Guam in 1944. “I hate the Republicans. They’re pulling all kinds of stuff trying to hold hostage things like this.”

The first partial government shutdown in 17 years shuttered national parks and government offices from coast to coast. It also sent hundreds of thousands of federal workers home after they reported to work to secure files, post closed signs on their doors and change voice-mail messages to inform callers they wouldn’t be working until the budget impasse was solved.

Jeanette Joyner, an Army budget analyst who survived the 2001 terrorist attack on the Pentagon, left her office today after getting a furlough notice, while bracing for the uncertainty to come. Joyner, 45, was one of an estimated 400,000 civilian defense workers put on furlough.

Absorbing the pain of a lost paycheck won’t come easy, she said.

“My office took a direct hit,” she said of the Sept. 11 terrorist attack in which American Airlines Flight 77 crashed into the Pentagon. “I crawled out of a bathroom. If I can survive 9/11 and come back to this building, I can survive this.”

Phil Young, a post-baccalaureate fellow with the Food and Drug Administration who is doing allergy research at National Institutes of Health, said he will continue to receive his stipend even though there is no work for him to do as a result of the shutdown. “This is an educational experience for me,” said Young, 24, who lives in Bethesda. “When I can’t come to the lab I just miss out on that.”

Young said he usually works about 40 to 50 hours a week at NIH, which he won’t be doing now.

“I’m going home,” he said.

From its Bethesda, Md., headquarters, NIH operates a hospital and conducts research on subjects including cancer, heart disease and the human genome. Now 73 percent of the agency’s 18,646 workers were furloughed. Most of those allowed to stay are being retained to provide care to patients and laboratory animals and to protect ongoing medical experiments, according to the agency’s contingency plan.

The shutdown brings to a halt all basic research, work on grant applications and the admission of new patients at NIH. People who have existing grants will still have access to those funds, according to an agency statement.

The Centers for Disease Control in Atlanta said it was shutting down its Twitter feed. “We’ll be back as soon as possible,” its last tweet read.

More important, the shutdown leaves the center with an impaired ability to monitor and track diseases and to perform routine laboratory inspections, said CDC spokeswoman Barbara Reynolds.

Out of 13,000 CDC employees, 9,000 won’t be working under the shutdown, Reynolds said. “What we see this shutdown doing is hurting our ability to find threats,” she said.

In Washington, Canden Schwantes said her DC By Foot business will suffer from the shutdown even as 14 people had booked a tour.

Four school groups have canceled already for the coming days, Schwantes said.

“It doesn’t matter if they reopen,” she said. “Those tours have already canceled. I’m out of a week of income.”

The tour normally goes into both the Library of Congress and the Capitol Visitors’ Center, both of which are closed today. Instead, Schwantes was leading tourists outside Senate and House office buildings, to the site where George Washington’s town homes used to sit, and the Japanese-American Memorial.

Ashon Nyanuttara was relying on his training as a Buddhist monk not to get frustrated or angry after he arrived in Battery Park in New York City this morning to find tours of the Statute of Liberty had been canceled.

“This is no good for public, especially tourists,” said Nyanuttara, 30, who is visiting New York from Myanmar. “This is an American symbol. The government should keep it open.”

Bette Rosenzveig, 68, said the month she spent training to walk up the statue’s 354 steps was now wasted because Washington couldn’t reach a deal. The Decatur, Georgia resident, put the blame squarely on the Republican Party for the shutdown.

“I believe the most important thing is to protect the American economy from Obamacare,” Weaver, who is the business manager of her husband’s medical practice, said in a telephone interview. “The long-term health of the economy is far more important than a shutdown,” Weaver said.

Back at the World War II Memorial, veterans from Iowa soon joined those from Mississippi in ignoring the barricade.

“It’s hard for us to see people not be let in,” Carol Johnson, a spokeswoman for the National Park Service’s National Mall and memorials division told reporters. “This memorial was built for them. And the last thing we want to is keep them from seeing it.”